70 Proceedings of the Biological Society of Washington. 



Diagnosis. — A member of the Rattus rattus group differing from Rattus 

 hoffmanni (Matschie), the common member of the group throughout 

 northern Celebes, in paler coloration; longer tail; less angular, more 

 rounded antorbital plate; and much smaller teeth. 



Measurements. — Type: Head and body, 178 mm.; tail, 220; hind foot, 

 36. Skull of type: Condylobasal length, 40.6; zygomatic breadth, 19.2; 

 palatal length, 23.3; mastoid breadth, 16.0; mandible, 23.7; maxillary tooth 

 row, crowns, 6.2; mandibular tooth row, crowns, 6.1. (Average measure- 

 ments of ten adults of hofftnanni: Tail, 195; maxillary tooth row, crowns 

 7.0.) 



Specimens examined. — Seven; two from Pulo Paleleh; four from Toli 

 Toli, and one from Molengkapoti, on the mainland of northern Celebes. 



Remarks. — There is in the collection a very extensive series of specimens 

 of Rattus hoffmanni from mainland localities on the northern peninsula of 

 Celebes, from Menado west and south to Laboea Sore, just north of Parigi. 

 The seven specimens of Rattus palelae are instantly separable from any 

 specimen of hoffmanni by the much smaller, especially narrower, teeth. In 

 addition to this diagnostic character, the specimens of palelae average 

 distinctly lighter, less richly colored, and have longer tails. Rattus hoff- 

 manni was not taken on Pulo Paleleh, but specimens with small teeth, and 

 in no way distinguishable from the new species, were collected at two main- 

 land localities on the northern coast where good series of hoffmanni were 

 also obtained. 



Rattus hoffmanni linduensis, subsp. nov. 



Type from Tornado, Lake Lindoe, Middle Celebes. No. 218,700, U. S. 

 National Museum; skin and skull of adult 9 (teeth moderately worn); 

 collected March 28, 1917, by H. C. Raven; original number 3141. 



Diagnosis. — Like Rattus hoffmanni hoffmanni (Matschie) of northern Ce- 

 lebes, but averaging smaller and darker; with longer, softer pelage; and 

 smaller skull. 



Measureynents. — Type: Head and body, 170 mm.; tail, 170; hind foot, 37. 



Skull of type: Condylobasal length, 38.9; palatal length, 21.9; zygomatic 

 breadth, 20.5; mastoid breadth, 16.7; interorbital breadth, 5.8; mandible, 

 25.2; maxillary tooth row, crowns, 7.4; mandibular tooth row, crowns, 7.5. 



Specimens examined. — Forty-nine, from the following localities in Middle 

 Celebes: Bumbarocdjaba; Koelawi; Lehio; Pinedapa; Rano Rano; Tomado, 

 Lake Lindoe. 



Remarks. — All of these specimens of Rattus hoffmanni from the highlands 

 of Middle Celebes are readily separable from specimens of the typical form 

 from North Celebes by the long, soft, richly colored pelage. The under- 

 parts average darker also, more grayish buff; the skulls average distinctly 

 smaller, but the teeth are large, as in the typical form. The specimens 

 from Bumbarocdjaba are clearly referable to linduensis rather than to true 

 hoffmanni which occurs near the coast, north of Toboli, at Laboea Sore. 



Rattus hoffmanni subditivus, subsp. nov. 



Type from Toware, Bada, Middle Celebes. No. 219,691, U. S. National 

 Museum; skin and skull of adult 9 (teeth moderately worn); collected 

 September 18, 1917, by H. C. Raven; original number 3270. 



